Looks like omap34xx OCP registers are not readable unlike on omap36xx.
We use SGX revision register instead of the OCP revision register for
34xx and do not configure any SYSCONFIG register unlike for 36xx.

I've tested that the interconnect target module enables and idles
just fine with PM runtime control via sys:

# echo on > $(find /sys -name control | grep \/5000); rwmem 0x5000fe10
# rwmem 0x50000014	# SGX revision register on 36xx
0x50000014 = 0x00010205
# echo auto > $(find /sys -name control | grep \/5000)
# rwmem 0x5000fe00
And when idled, it will produce "Bus error" as expected.

Cc: Adam Ford <aford173@gmail.com>
Cc: Filip Matijević <filip.matijevic.pz@gmail.com>
Cc: "H. Nikolaus Schaller" <hns@goldelico.com>
Cc: Ivaylo Dimitrov <ivo.g.dimitrov.75@gmail.com>
Cc: moaz korena <moaz@korena.xyz>
Cc: Merlijn Wajer <merlijn@wizzup.org>
Cc: Paweł Chmiel <pawel.mikolaj.chmiel@gmail.com>
Cc: Philipp Rossak <embed3d@gmail.com>
Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Tested-by: Adam Ford <aford173@gmail.com> #logicpd-torpedo-37xx-devkit
Signed-off-by: Tony Lindgren <tony@atomide.com>